New Delhi: Facing embarrassment over allegations by a top government official that torture by its officers drove him and his family to suicide, CBI on Thursday deputed a joint director level official to probe the charges.

National Human Rights Commission has asked CBI director Anil Sinha to give a report on the allegations within 72 hours.

The then director general corporate affairs, BK Bansal, in his purported suicide note had accused a DIG-level official and three more officers of torturing his wife and daughter to an extent that they ended their life soon after his arrest in July on corruption allegations.

A file photo of BK Bansal. CNN News 18

Bansal and his son allegedly ended their lives on 27 September. He sent his purported suicide note dated a day before to PTI in which he alleged that the DIG, an Indian Revenue Service Officer of Customs and Excise Branch, had flaunted his connections with a powerful politician of ruling party.

It is rare for CBI to have a DIG level official from any service other than Indian Police Service, a former CBI official requesting anonymity said.

The officer had alleged that the DIG had dared him to do whatever he likes saying he "is the man" of that politician and nobody can touch him.

"Even if I was at fault, why my wife and daughter were tortured? They did not commit suicide. It was murder of two 'ladies'," Bansal had alleged.

CBI sources said since the allegations are related to the conduct of an officer in an ongoing investigation, an internal probe has been ordered. They said a joint director level officer has been entrusted to probe the allegations and submit report as soon as possible.

Bansal's son Yogesh in his two page purported suicide note alleged that he was "unofficially" subjected to "mental and physical" torture to an extent that he is forced to take such a step. He alleged that the five CBI officers including the DIG had "unofficially and off the record tortured him, his mother and his sister".

"My mother and my sister were against suicide but they were tortured to such an extent that they took the step," he alleged, adding that they were "murdered" by CBI officers and supported by a neighbour who made fun of their situation.

Bansal, an additional secretary-rank officer in the Ministry of Corporate Affairs, was arrested by CBI on 16 July for allegedly accepting bribe from a prominent pharmaceutical company.

"We have examined the matter and decided to probe the allegations. CBI is fully committed to conduct investigation in a fair and professional manner without harassment to any one and strictly within the parameters of law.

"If any violation is established during the probe, strict action will be taken against the CBI officials concerned. The Competent Court will be informed," CBI Spokesperson had said.